Testing Filter Presence in Angular

Question

I'm new to unit testing and trying to grasp things. I'm doing my best to follow this tutorial: http://www.yearofmoo.com/2013/01/full-spectrum-testing-with-angularjs-and-testacular.html#testing-filters. In my AngularJS app I have a filter that I need to test. I have Node, Testacular, and Jasmine set up and running properly. The filter I am trying to test is pretty simple:

myApp.filter('bill_ship', function () {
    return function (userData) {
        var output = "---";
        switch (userData) {
            case "0":
                output = "Billing";
                break;
            case "1":
                output = "Shipping";
                break;
        }
        return output;
    }
});

I thought I had my test set up correctly, but it consistently fails.

describe("Unit Testing: Filters - ", function() {
    beforeEach(angular.mock.module('prismApp', ['bill_ship']));

    //BillShip Filter
    it('should have a bill-ship filter: ', inject(function($filter){
        expect($filter('bill_ship')).not.toEqual(null);
    }));
});

It fails with this message: Error: Argument 'fn' is not a function, got string from bill_ship.

So... where am I doing this wrong?

Answer 1

If anyone else is wondering (I spend some time before I found out) I thought that @MBielski's way of injecting filters was a little confusing, but deffinately does the job! However, I found this to be a good way to inject filters into jasmine unit test environment to test them.

Here's the filter definition:

angular.module('prismApp.filters', [])

  .filter('billShip', function () {
    return function (userData) {
      // define filter
      ...
    }
  });

And the test:

describe("Unit Testing: Filters - ", function() {
  var billShip;

  // load the module
  beforeEach(module('prismApp.filters'));

  // load filter function into variable
  beforeEach(inject(function ($filter) {
    billShip = $filter('billShip');
  }));

  // test billShip filter
  it('should have a bill-ship filter: ', function () {
    // test away!
    expect(billShip).not.toEqual(null);
    expect(billShip("0")).toEqual("Billing");
    ...
  });
});

Hope this helps anyone else.

Answer 2

Ok, this why I should never code without caffine...

It helps a LOT when you put the files that you want to test in the config file. Boy do I feel stupid.